Show DepthEdge: don't show edge weight
Various graph visualization libraries use the Show
instance as the label for edges, and right we're more
interested in the venue+market than the opaque floating
point number that is the edge weight.
Paths: remove "toEdgeM" debug print
Util: add "trim" function
"trim" trims a graph so that it contains, at most, a specified number
The edges with the "largest" edge labels (as defined by the edge label
comparison function) that are connected to the remaining nodes are
Revert: "RateMap: write graph to graphviz dot file"
Merge branch 'debug-ratemap'